The present invention relates to a unidirectionally penetrable (or one-way see-through) ornamental film that is applied to a glass window, a transparent acrylic plate or the like.
Hitherto, a unidirectionally penetrable film called oneway vision has been known. This comprises a film painted in a light-shielding color such as black on one surface thereof and in white on another surface thereof, and a pressure sensitive adhesive layer and a separator provided on the light-shielding color surface. The film is perforated with a number of throughholes of a diameter of approximately 1 to 2 mm in an opening ratio of approximately 30 to 70%. When in use, the separator is peeled off and then applied to a glass window of a room. When viewing the outside from inside the room in a daytime through the film, one views a bright world through a number of throughholes arranged overall the light-shielding color surface, so that he or she can see the outside through it, with a feeling that the eyesight has not been blocked so much due to illusion of sight. On the contrary, when viewing the inside of the room from outside through the film, it is almost impossible for one to view the inside since he or she views the darker world through the throughholes. In this manner, oneway vision film has a function of a blind against seeing from one direction while sufficiently maintaining an eyesight from another direction.
Recently, various images have been laid on the white surface of such a unidirectionally penetrable film in order to improve advertising or amenity effects. At present, in order to lay an image on the white surface of the film for that purpose, an image recorded on an electrostatic recording paper using a color electrostatic plotter is transferred to the white surface of a film by heat-pressing. This is because the principle can be utilized that a 3 to 5 xcexcm-thick dielectric layer (composed of a resin) onto which an image is fixed can be peeled off as a whole by giving moisture to it or by heating it.
The film used in the method described above has the structure in which an image is laid on its white surface and a pressure sensitive adhesive layer is laminated on the light-shielding color surface and in an in situ operation, the film is applied to the outer side of a glass window. The film applied to the outer side when viewed from the outside has the defect of losing the feeling of transparency inherent to the glass window that would otherwise be retained. Other defects of this film are as follows. It tends to be peeled off from the glass. The throughhole portion comprises protrusions and depressions so that it is readily befouled and difficult to clean. In this case, the thin resin film of the dielectric layer containing the transferred image is designed to cover the throughholes, which also damages the transparent feeling of throughholes. In addition, the image as it is not resistant to light under direct sunshine. To improve the light resistance of the image, there is no way other than laminating an ultraviolet ray shielding film, which not only further deteriorates the transparent feeling but also increases the production costs.
Therefore, a unidirectionally penetrable film having improved advertising and amenity effects that maintains transparent feeling of a glass window and that of throughhole portion, is hardly peeled off from the glass window, is hardly befouled and has light resistance is keenly desired.
The present inventors previously disclosed the technology on the xe2x80x9cmethod for fabricating an imaged filmxe2x80x9d (Japanese Patent No. 2,934,948 (U.S. Pat. No. 5,789,341).
This is a technology using a laminate film comprising a transparent resin film in which a sublimable dye can be diffused and a white resin film that has no affinity for a sublimable dye, and a transfer paper on which an image has been recorded with an ink containing a sublimable dye is contacted and heated to diffuse the sublimable dye through the white resin film into the transparent resin film to develop a transferred image on the side of transparent film.
This technology shows that upon heating, a sublimable dye is imagewise transferred through a laminate film comprising a white resin film that has no affinity for the sublimable dye and a transparent resin film that allows diffusion of the sublimable dye therein by diffusing from the surface of the white resin film to the side of the transparent resin film on the opposite side of the laminate film independently of color.
The present inventors have made extensive studies with a view to solving the problems of the unidirectionally penetrable film described above and as a result they have found that use of an ornamental film comprising a laminate having a transparent resin film in which a sublimable dye is diffusible, a white coating layer on the transparent resin film, and a light-shielding color coating layer on the white coating layer, in which resins that constitute the white coating layer and the light-shielding color coating layer have no affinity for the sublimable dye can fundamentally dissolve the above-described problems. The present invention is based on this discovery.
More particularly, by superimposing a transfer paper having recorded thereon an image with an ink containing a sublimable dye onto the light-shielding color surface of the ornamental film and contacting the transfer paper therewith and heating the transfer paper, the sublimable dye on the transfer paper can be passed through the light-shielding color coating layer and white coating layer to thereby transfer the dye to the transparent resin film in a high density. On this occasion, if a pressure sensitive adhesive layer and a separator thereon are further provided on the side of the transparent resin film, a transferred image appears so that it can be viewed from the side of the pressure sensitive adhesive layer. In this state, the separator can be peeled off and the pressure sensitive adhesive layer of the ornamental film having the transferred image backed by the white coating layer can be applied as it is to the inner side of a glass window. Throughholes, if any, formed in the ornamental film in a predetermined opening ratio make it possible to use the ornamental film as a unidirectionally penetrable ornamental film through which the outside can be viewed clearly from the inside the glass window but the inside cannot be viewed from the outside.
That is, the present invention provides the following unidirectionally penetrable ornamental film before image transfer and unidirectionally penetrable ornamental film after image transfer.
1. A unidirectionally penetrable ornamental film comprising a laminate having a transparent resin film 3 in which a sublimable dye is diffusible, a white coating layer 2 on the transparent resin film 3, a light-shielding color coating layer 1 on the white coating layer 2, a pressure sensitive adhesive layer 4 on a surface of the transparent resin film 3 opposite to a surface on which the white coating layer 2 is provided, and a separator 5 on the pressure sensitive adhesive layer 4, wherein resins that constitute the white coating layer 2 and the light-shielding color coating layer 1 have no affinity for the sublimable dye.
2. A unidirectionally penetrable ornamental film according to 1 above, wherein the transparent resin film 3 comprises a laminate film having a transparent resin support film 3a and a transparent coating layer 3b in which the sublimable dye is diffusible, the transparent coating layer being laminated on the transparent resin support film 3a. 
3. A unidirectionally penetrable ornamental film according to 1 above, wherein the resin having no affinity for the sublimable dye is selected from the group consisting of a fluoro resin, a silicone resin and an olefin resin.
4. A unidirectionally penetrable ornamental film according to 1 above, wherein the light-shielding color of the light shielding color coating layer 1 is a color selected from the group consisting of black, intense dark achromatic color and intense dark chromatic color.
5. A unidirectionally penetrable ornamental film according to 1 above, wherein the transparent resin film 3 contains an ultraviolet absorbent.
6. A unidirectionally penetrable ornamental film according to 2 above, wherein at least one of the transparent resin support film 3a and transparent coating layer 3b contains an ultraviolet absorbent.
7. A unidirectionally penetrable ornamental film according to any one of 1 to 6 above, wherein the ornamental film is formed with throughholes 6 having an area of 10 mm2 or less in an opening ratio of 30 to 70% overall surfaces thereof.
8. A unidirectionally penetrable ornamental film according to 7 above comprising a dye image on the light-shielding color coating surface of the ornamental film, the image being obtained by superimposing a transfer paper having recorded thereon an image with an ink containing a sublimable dye, contacting the transfer paper with the ornamental film and heating the transfer paper to pass the sublimable dye through the light-shielding color coating layer and the white coating layer to thereby transfer the dye to the transparent resin film in a high density.
9. A unidirectionally penetrable ornamental film, comprising a transparent resin film 3 in which a sublimable dye is diffusible, a white coating layer 2 on the transparent resin film 3, and a light-shielding color coating layer 1 on the white coating layer 2, wherein the transparent resin film 3 is dyed with an image comprising the sublimable dye and is formed with throughholes 6 having an area of 10 mm2 or less in an opening ratio of 30 to 70% overall surfaces thereof, the ornamental film being applied to a transparent element on the side of the transparent film.